Field
Compound semiconductor devices.
Description of Related Art
Compound semiconductor devices are viewed as promising alternatives or complements to silicon-based devices. Compound semiconductor may be described generally as binary or tertiary group III-V semiconductor materials. The group III-V reference denotes elements in group XIII and XV of the periodic table, respectively. The group III and group V notations reference the former International Union of Pure Applied Chemistry (IUPAC) numbers.
A binary compound semiconductor such as gallium nitride has a wurzite crystal structure and a crystal polarity. Gallium nitride high electron mobility transistors (HEMTs) are used in wireless infrastructure applications. Gallium nitride base metal oxide semiconductor field effect transistors (MOSFETs) and metal semiconductor field effect transistors (MESFETs) also offer advantages in high power electronics.
Heterogeneous integration schemes generally involve integration of different semiconductor materials to make a virtual substrate. Layer transfer of a semiconductor layer to a substrate is a promising method to make a virtual substrate, because a relatively thick buffer layer may be avoided between lattice mismatched materials. In terms of the viability of layer transfer of gallium nitride, gallium nitride fabrication schemes tend to prefer a certain crystal polarity, namely positive or +c surface polarity. Efforts to transfer a polar compound semiconductor layer such as gallium nitride layer fabricated according to such schemes tend to result in a transfer of a semiconductor layer with a +c polar surface available for a device formation.